Fixing bad drills

[Jupiter 2.9]

I have a few bodies that I have cut weight pockets for & the rear drill came out poorly.
I need to fill the holes & re drill them, maybe save a couple of bad builds on my part.

? 2 part epoxy, 5 minute epoxy, wood glue ?

A new block is only $5 but I can give the re drills to the Scouts next year if they don't meat league standards.

 

[HurriCrane Racing]

What i do is fill the axle hole by using wood glue and a toothpick. Put wood glue in the axle hole and insert a toothpick.
Let dry and then redrill.

I would not recommend using epoxy. I have tried filling the slots of a scout block with epoxy and drilling in the past. Never worked out very well.

 

[Jupiter 2.9]

I forgot about the toothpick thing, wasn't thinking.
wood glue & toothpick would match the original wood.
Thanks

 

[TRE]

Start over...never had goodluck filling and redrilling

 

[Roadrunner]

+1 on hurriCranes’ method. I’ve had many bad drills as part of my learning process. No luck with epoxy. It’s much harder than the surrounding wood. It will deflect your drill bit. I think the same thing happens with wood glue and toothpick, but to a lesser degree. Probably still good enough for scout racers... But I’m with TRE, I start over if my drill goes bad.

 

[Roadrunner]

One last thought on verifying your drilling - don’t assume that your gauge pin is straight. I learned that one the hard way...

 

[T-Bone Racing]

Start over...never had goodluck filling and redrilling

Although the wood glue and toothpick idea is the best problem solver, starting over is best, because you shouldn’t be too far into the build, So there shouldn’t be too much time invested yet, and one plank of wood shouldn’t have more than one chance in my opinion.

 

[Jupiter 2.9]

Thanks Ya'll
I run them down the tuning board after a visual pin gauge check before I get to far gone.

I have a Hurricane on my doorstep so I was kinda filling up my weekend stuck in the house.
& I have plenty of bad blocks

 

[Brian Stanley]

I drill a block twice, once at each end, if neither is good it goes in the burn bag for camping trips. Let's just say the burn bag is getting quite full!

 

[Ballistic Racing]

I’ve never filled & redrilled the rears, but have done the front steer. I used a 1/16 dowel sanded down to fit snug with wood glue.
Worked great.

 

[ljo]

If you are feeling patient, you can router out the bad drill and fill it in with fresh wood and try again. Just kidding, don't do this. It's not worth the effort.

 

[OneSpartan]

I drill a block twice, once at each end, if neither is good it goes in the burn bag for camping trips. Let's just say the burn bag is getting quite full!

I do the same thing. Drill one end, test it. If I don't like it, drill the other end and test it. I've tried to fill and re-drill and have never been successful. Now I just go the quantity method and save the good ones. That said, my success rate has improved substantially with the Silver Bullet. Ill offer up the B grade ones to my sons pack. No one drills their own so these are a huge upgrade.

 

[Jupiter 2.9]

So a few weeks ago I organized my drill bits, I have 2 jigs that I use so I test fit every bit that I had for each.
Come to find out I only have 4 bits out of a dozen that are actually a snug fit,
Lesson learned. .0001

 

[HurriCrane Racing]

So a few weeks ago I organized my drill bits, I have 2 jigs that I use so I test fit every bit that I had for each.
Come to find out I only have 4 bits out of a dozen that are actually a snug fit,
Lesson learned. .0001

That is exactly what I have found as well. Without a well fitting drill bit, your drills will be inconsistent.

 

[Brian Stanley]

So a few weeks ago I organized my drill bits, I have 2 jigs that I use so I test fit every bit that I had for each.
Come to find out I only have 4 bits out of a dozen that are actually a snug fit,
Lesson learned. .0001

I've been diving into the rabbit hole of hobby machining, and something that has been a bit maddening for me is that bits appear to be undersized. I ordered 10 #43 and 10 #44 bits from McMaster Carr, everyone of them was about .002 under it's stated size. I finally decided that they must do that on purpose, I suppose they're trying to account for the runout in the end user's hole making tool. Undersize them so the hole they create is closer to spec. Of course when I'm drilling metal I undersize and then ream to get where I need to go, but that doesn't really help with these PWD drill jigs.

 

[Roadrunner]

Brian Stanley said: I've been diving into the rabbit hole of hobby machining...

That’s great! Another home shop machinist. I’d bet there are several of us here...

 

[Brian Stanley]

Brian Stanley said: I've been diving into the rabbit hole of hobby machining...

That’s great! Another home shop machinist. I’d bet there are several of us here...

I used to think 1/16ths of an inch was SO small.......

 

[Roadrunner]

... and now we’re trying to work a block of wood in thousandths

 

[Castoro Racing]

Brian try going to your local hardware store and test fit their bits in your jig